In the traditional sailboats, both single and multihull, the masting consists of a mast disposed on the longitudinal axis of the hull, which is supported by a plurality of shrouds and stays with eventually the aid of one or more pairs of crosstrees. This masting exhibits a series of structural and aerodynamic drawbacks. Under rest condition, the mast is compressed by symmetrical forces imposed by the rigging, while the shrouds and the stays are uniformly tensioned. Under wind-blowing condition, vice-versa, only the windward rigging is acted upon, resulting in heavy tensile stress, while the leeward rigging is partially unloaded or even in a slack condition, that is, released from the tension it is subject when at standstill. As a consequence, under a wind blowing condition, the mast is under a combined compression and bending stress, while the stress over the rigging is distributed only over a portion thereof, with consequent overstressing of the windward shrouds and of the hull at the anchorage points of the windward shrouds.
The structural problems related to the mastings the traditional type are even greater in the case of multihull boats. In fact, with catamarans, for example, the mast is borne by the structure connecting the two floats, while the shrouds are applied to the same floats. As the mast is under compression, the connection structure between the floats is stressed by high bending moments dynamically varying during the navigation. This gives rise to frequent breaks of such connection structures. A similar thing occurs with the trimarans, in which the mast is supported by the central float and the shrouds are anchored to the side floats. The connection structures are still subject to high bending moments of a dynamic nature during the navigation.
Moreover, the presence of the mast makes it compulsory to attach the main sails, especially jib and spanker, in correspondence of the boat central axis. This implies heavy restraints as far as the aerodynamic solutions of the sails are concerned; for example, with a traditional masting, the possible minimum value of the angle between the boat route and the real direction of the wind is about 45.degree. (corresponding to the angle taken up by the boat during a close-hauled sailing). A smaller angle between the wind real direction and the boat route is not feasible.